Barium ferrite is a kind of magnetic material used in magnetic powder, square magnetic steel, magnetic film, and toys.
Used to manufacture homotropic magnets, magnetic films, toys
Crystal characteristics of barium ferrite
Barium Ferrite (BaFe12O19) is a hard magnetic material belonging to M-type magnetoplumbite. It is a relatively simple magnetoplumbite ferrite with hexagonal symmetry and belongs to the hexagonal system. Its crystal structure is different from spinel ferrite, because it contains barium (Ba) and lead (Pb) plasma, and its radius is similar to oxygen ions (1.32nm), so it cannot enter the gap formed by oxygen ions Its radius is similar to oxygen ion (1.32nm) and can only be in the same layer with oxygen ion. Its crystal structure is not cubic symmetry but hexagonal symmetry. The symmetry of the hexagonal crystal is lower than that of the hexagonal crystal, so its magnetocrystalline anisotropy is extraordinarily large. Each BaFe12O19 unit cell includes two molecules, which can be divided into 10 oxygen ion layers. The close-packed arrangement of oxygen ions in the c-axis direction can be divided into several layers and blocks. The oxygen ion layer including Ba2+ is called the barium layer and is represented by B1. This B1 layer appears every four oxygen ion layers. Each B1 layer includes one Ba2+ and three Fe3+, two of which occupy the B site, and one occupies the six-sided position composed of five oxygen ions, also called the E site.
The importance of magnetoplumbite ferrite is that it has certain characteristics due to its crystal symmetry that the other two types of ferrites with cubic symmetry do not have.
Preparation method of barium ferrite
Because barium ferrite is widely used in permanent magnetic materials and perpendicular recording materials, the synthesis of ultrafine barium ferrite powders with small particle size, uniform chemical composition, and high performance is the main direction of magnetic materials research nowadays. There are many methods for synthesizing barium ferrite ultrafine powder, the main methods are: co-precipitation, hydrothermal crystallization, metal organic hydrolysis, glass crystallization, organic resin, sol-gel, and spray pyrolysis Wait.
to sum up
Nano-magnetic technology is the dominant technology in the first 20 years of this century. Nano-magnetic materials are the core of nano-magnetic technology, the most promising material in the 21st century, and one of the application foundations of nano-magnetic technology. The development of nano-magnetic technology has brought major opportunities and challenges for the traditional magnetic industry to develop by leaps and bounds. The development and research of nano-scale magnetic materials is an inevitable direction for the development of magnetic materials, but at the same time, attention should be paid to the use of nano-technology to transform traditional industries and Research on nano-magnetic modification of existing materials in order to comprehensively improve the technical level and competitiveness of enterprises, and establish the banner of the Chinese nation among the nations of the world